KR20130139022A - A conductive paste composition - Google Patents

Abstract

The present invention relates to conductive paste compositions for photovoltaic cells with an excellent aspect ratio, capable of improving electrical characteristics. Specifically, the conductive paste composition comprises; (a) hydrophilic conductive metal, hydrophobic vehicle, glass frits and additives; or (b) hydrophobic conductive metal, hydrophilic vehicle, glass frits and additives; and the hydrophobic vehicle includes hydrophobic binders and hydrophobic solvents whereas the hydrophilic vehicle includes hydrophilic binders and hydrophilic solvents.

Description

A conductive paste composition

The present invention relates to a conductive paste composition for a solar cell electrode which can improve the characteristics of the solar cell by eliminating the spread of the line width after screen printing and easy to adjust the line width to improve the electrical properties by increasing the fine line width and aspect ratio.

The front electrode of the solar cell is mainly formed through a screen printing process. Therefore, the front and rear electrode paste compositions are also manufactured in consideration of the printability of the screen printing process, but in particular, the front electrode is difficult to realize a good resolution by reproducing a desired line width.

For example, the conventional method uses a silver conductive paste composition for the front electrode, and even if the line width of the screen printing mask for the front electrode is 80 μm, the line width of the front electrode is 10 to 20 μm wider after actual printing. many. As a result, the light receiving surface of the cell is reduced, and as a result, a problem of deterioration of battery characteristics occurs.

In addition, most of the existing compositions are intended to maximize the dispersibility of the paste by selecting the inorganic surface treatment agent and the organic material with the same series of properties for the dispersion of the inorganic material in the paste. However, if the optimal composition is not selected, it is difficult to form an electrode having desired characteristics because of the wide spread of the line width or the high surface roughness after printing.

In addition, Korean Patent Publication No. 2011-0011974 discloses a method of coating a hydrophilic material on a hydrophobic film by separately dropping the hydrophilic solution after applying heat to the hydrophobic film and evaporating the solvent. However, in the above method, since only the hydrophobic film is coated by dropping the hydrophilic solution, the composition of the hydrophilic solution may not be known, and the fine line width at the time of forming the electrode of the solar cell may not be realized, and line width spread or surface roughness may occur.

In the present invention is to provide a conductive paste composition that can realize a very excellent resolution by the composition development through a combination of a hydrophilic conductive metal, a hydrophobic binder and a hydrophobic solvent or a combination of a hydrophobic conductive metal, a hydrophilic binder and a hydrophilic solvent.

In another aspect, the present invention is to provide a conductive paste composition that can improve the characteristics of the solar cell by increasing the aspect ratio and the improvement of the electrical properties by eliminating the spread of the line width.

The present invention includes (a) a hydrophilic conductive metal, hydrophobic vehicle, glass frit and additives, or (b) a hydrophobic conductive metal, hydrophilic vehicle, glass frit, and additives,

The hydrophobic vehicle comprises a hydrophobic binder and a hydrophobic solvent,

The hydrophilic vehicle includes a hydrophilic binder and a hydrophilic solvent,

Provided is a conductive paste composition.

Preferably, the present invention comprises 40 to 90% by weight hydrophilic conductive metal, 1 to 20% by weight hydrophobic binder, 1 to 30% by weight hydrophobic solvent, 1 to 10% by weight glass frit, and 0.01 to 5% by weight additive. Paste compositions can be provided.

The present invention also provides a conductive paste composition comprising 40 to 90% by weight hydrophobic conductive metal, 1 to 20% by weight hydrophilic binder, 1 to 30% by weight hydrophilic solvent, 1 to 10% by weight glass frit, and 0.01 to 5% by weight additive. Can be provided.

In addition, according to the present invention, there is provided a solar cell comprising an electrode formed using the above-mentioned conductive paste composition. Preferably, the present invention provides a solar cell comprising a front electrode having an aspect ratio of 20 to 35% and a series resistance (Rs) of 3 or less.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a paste composition capable of realizing a desired line width by performing screen printing using a paste made of a hydrophilic conductive metal and a hydrophobic vehicle or a combination of a hydrophobic conductive metal and a hydrophilic vehicle.

The present invention can realize the desired line width by using the composition consisting of the above combination can ensure a sufficient light receiving area of the solar cell in the solar cell. Therefore, the present invention can improve the solar cell efficiency by preventing the loss of Isc.

In addition, the paste made of the hydrophilic conductive metal and the hydrophobic vehicle or the combination of the hydrophobic conductive metal and the hydrophilic vehicle can be designed to have a high thixo index (TI) value, thereby achieving a high aspect ratio at a constant line width. You can get it. Therefore, the present invention can ensure a low resistance even at the same line width can lower the Rs value of the solar cell and consequently improve the solar cell efficiency.

In addition, the paste prepared according to the present invention exhibits a rheological property suitable for screen printing, and thus has a mask masking property in a shear rate section at the time of printing even when the viscosity is high in a low shear rate section. have. Therefore, according to the present invention, it is possible to implement fine line width because of excellent omission in fine line width and excellent printability.

Further, in the present invention, by applying a composition having different properties of the surface treatment agent and the organic material of the inorganic material, by selecting the optimum combination of these properties so that these properties can affect the dispersibility and printability of the paste to achieve fine line width and high Aspect ratio implementation is now possible.

Specifically, according to a preferred embodiment of the invention, (a) a hydrophilic conductive metal, a hydrophobic vehicle, a glass frit and an additive, or (b) a hydrophobic conductive metal, a hydrophilic vehicle, a glass frit, and an additive, said hydrophobic vehicle A conductive paste composition is provided comprising a silver hydrophobic binder and a hydrophobic solvent, wherein the hydrophilic vehicle comprises a hydrophilic binder and a hydrophilic solvent.

The present invention can improve the aspect ratio of the electrode after printing by using a metal and a binder of different properties, and can implement a fine line width, and as a result can lower the resistance of the electrode can improve the efficiency of the solar cell.

Accordingly, the present invention provides a paste composition comprising a hydrophilic conductive metal and a hydrophobic vehicle, and comprising a glass frit and an additive thereto. The hydrophobic vehicle can be prepared using a hydrophobic binder and a hydrophobic solvent.

The present invention also provides a paste composition comprising a hydrophobic conductive metal and a hydrophilic vehicle, comprising a glass frit and an additive. The hydrophilic vehicle can be prepared using a hydrophilic binder and a hydrophilic solvent.

In addition, the conductive paste composition of the present invention (a) 40 to 90% by weight hydrophilic conductive metal, 1 to 20% by weight hydrophobic vehicle, 1 to 10% by weight glass frit and 0.01 to 5% by weight additives, or (b) hydrophobic conductive metal 40 to 90 weight percent, 1 to 20 weight percent hydrophilic vehicle, 1 to 10 weight percent glass frit and 0.01 to 5 weight percent additives.

In the hydrophobic vehicle, the weight ratio of the hydrophobic binder and the hydrophobic solvent may be 0.5: 9.5 to 3: 7. In addition, the weight ratio of the hydrophilic binder and the hydrophilic solvent in the hydrophilic vehicle may be 0.5: 9.5 to 3: 7.

More preferably, according to the first embodiment of the invention, 40 to 90% by weight hydrophilic conductive metal, 1 to 20% by weight hydrophobic binder, 1 to 30% by weight hydrophobic solvent, 1 to 10% by weight glass frit, and 0.01 to 10% additives There is provided a conductive paste composition comprising 5% by weight.

In the present invention, the hydrophilic conductive metal may be one or more selected from the group consisting of Ag, copper, nickel, Au, and silver coated metals having an average particle diameter of 0.1 to 5 μm, which are not coated or subjected to hydrophilic surfactant treatment. The hydrophilic surfactant treatment in the group consisting of polysorbitol, sorbitan fatty acid esters, polyglycerin (glycerol) fatty acid esters and oxyethylene (oxyethylene) series It can proceed using any one or more selected. For example, the surface treatment of Tween, Triton, SDS (SLS), and CTAB series can be performed during hydrophilic surfactant treatment. In addition, the silver coated metal may be one in which a silver powder is coated on a conductive metal such as Ag, copper, nickel, Au, or the like at a predetermined thickness, for example, 1 nm to 50 nm. In the present invention, the hydrophilic conductive metal is preferably coated with Ag having an average particle diameter of 0.1 to 5 μm, which is not coated or subjected to hydrophilic surfactant treatment, and in this case, the conductive paste composition provides a silver paste composition which is more effective than before. can do.

In the present invention, when the hydrophilic conductive metal is subjected to the above-described hydrophilic surface active treatment, the aggregation phenomenon between the Ag powders can be controlled in the paste as compared with the case where the surface treatment is not performed, and the different properties of the hydrophilic surface treatment agent, the vehicle, and the binder are different. This allows the TI value of the paste to be controlled, thus improving aspect ratio after printing. Such synergy can further improve solar cell efficiency.

The content of the hydrophilic conductive metal may be used in an amount of 40 to 90% by weight based on the total composition. When the content is less than 40% by weight, the dispersibility of the paste is good, but the resistance is high, and there is a limit in increasing the aspect ratio of the electrode after printing. As a result, no increase in efficiency can be expected. In addition, if the content exceeds 90% by weight, since the viscosity of the paste is high, dispersibility and printability are not good, there is a problem that disconnection and continuous printing are impossible during printing.

The hydrophobic binder is at least one selected from the group consisting of acrylic resins, epoxy resins, polyester resins, polyurethane resins, amino resins, phenol resins, vinyl resins, ethyl cellulose, polymethacrylates, monobutyl ethers and polyvinyl resins. Can be used.

The content of the hydrophobic binder is preferably used in 1 to 20% by weight based on the total composition. If the content of the hydrophobic binder is less than 1% by weight, there is a problem in that the amount of the binder is insufficient to sufficiently disperse the inorganic material in the paste. If the content of the hydrophobic binder exceeds 20% by weight, the dispersibility of the paste may be improved. There are many problems that the electrode resistance increases.

The hydrophobic solvent may be one or more selected from the group consisting of terpineol, butyl carbitol, butyl carbitol acetate, texanol, butyl cellulsolve acetate, butyl cellulsolve, diethylene glycol ethyl ether, and hexylene glycol. .

The content of the hydrophobic solvent is preferably used in 1 to 30% by weight based on the total composition. When the content of the hydrophobic solvent is less than 1% by weight, there is a limit to sufficiently dissolving the necessary binder, there is a problem in printability because a high viscosity paste is prepared, and when the content exceeds 30% by weight, a low viscosity paste is prepared, so the aspect ratio in printing There is a problem with limiting the increase.

The glass frit may be used as an inorganic binder, and at least one selected from the group consisting of Bi ₂ O ₃ based, Si-B-Pb based, Si-Bi-Zn based and Si-Pb-Al-Zn based may be used.

The content of the glass frit is preferably used in 1 to 10% by weight based on the total composition. If the content of the glass frit is less than 1% by weight, a lot of voids occur during sintering of the electrode, and there is a problem in that the adhesion between the solar cell substrate and the electrode is weakened. There is a growing problem.

The additive may use one or more selected from the group consisting of sintering aids, dispersants, antifoaming agents, thickeners, thixotropic agents and stabilizers.

The amount of the additive is preferably used in 0.01 to 5% by weight based on the total composition. When the content of the additive is less than 0.01% by weight, there is a problem in that it does not sufficiently affect the properties of the paste because it does not play a role of the additive in the paste, and when it exceeds 5% by weight, the printability and sintering properties of the paste are excessively affected. Paste property control is difficult.

The method of manufacturing the conductive paste composition may be prepared using a mixer used for preparing the paste. In addition, the glass frit is added to the vehicle composed of a hydrophobic binder and a hydrophobic solvent and mixed firstly, and the hydrophilic conductive metal and the additive are added and mixed secondly, and then, may be manufactured through a grinding process using a grinding apparatus. . The grinding device may be a grinding device well known in the art such as bead mill, three-roll mill and the like.

According to a second embodiment of the invention, 40 to 90% by weight hydrophobic conductive metal, 1 to 20% by weight hydrophilic binder, 1 to 30% by weight hydrophilic solvent, 1 to 10% by weight glass frit, and 0.01 to 5% by weight additive There is provided a conductive paste composition comprising a.

The hydrophobic conductive metal may be one or more metal powders selected from the group consisting of Ag, copper, nickel, Au, and silver coated metals having an average particle diameter of 0.1 to 5 μm coated with a fatty acid. In addition, the silver-coated metal used for coating treatment with the fatty acid may be one in which a silver powder is coated on a conductive metal such as copper, nickel, Au, or the like at a predetermined thickness, for example, 1 nm to 50 nm.

The fatty acid may be a substance well known in the art, but preferably fatty acids such as oleic acid, stearic acid, palmitic acid and acetic acid. In addition, the fatty acid is preferably coated with a thickness of 0.1nm to 50nm on the conductive metal. The fatty acid coating may be performed by adding a general metal such as silver powder (Ag powder) to the organic solvent in which the fatty acid is dissolved, stirring the mixture for a predetermined time, and then filtering.

The content of the hydrophobic conductive metal may be used in an amount of 40 to 90% by weight based on the total composition. When the content is less than 40% by weight, the dispersibility of the paste is good, but the resistance is high, and there is a limit in increasing the aspect ratio of the electrode after printing. As a result, there is a problem that cannot be expected to increase efficiency, and when the content exceeds 90% by weight, since the viscosity of the paste is high, dispersibility and printability are not good, there is a problem that disconnection and continuous printing are impossible during printing.

The hydrophilic binder is polyethylene glycol, polyvinyl alcohol, polyvinylacetate, polyacrylamide, polyacrylic acid, polymethacrylic acid, polyethylene oxide, methyl lactate, ethyl lactate, propyl lactate, aqueous polyurethane, hydroxyethyl cellulose , At least one selected from the group consisting of hydroxypropyl cellulose, ethyl hydroxyethyl cellulose, methyl cellulose and hydroxyalkyl methyl cellulose can be used.

The content of the hydrophilic binder is preferably used in 1 to 20% by weight based on the total composition. If the content of the hydrophilic binder is less than 1% by weight, there is a problem in that the amount of the binder is insufficient to sufficiently disperse the inorganic material in the paste. If the content of the hydrophilic binder exceeds 20%, the dispersibility of the paste may be improved, but voids and xanthan generated during the firing process may be generated. There are many problems that the electrode resistance increases.

The hydrophilic solvent may be used at least one selected from the group consisting of butoxyethanol, isopropyl alcohol, ethylene glycol, acetone, methanol and ethyl acetate.

The content of the hydrophilic solvent is preferably used in 1 to 30% by weight based on the total composition. When the content of the hydrophilic solvent is less than 1% by weight, there is a limit to sufficiently dissolving the necessary binder, there is a problem in printability because a high viscosity paste is prepared, and when the content exceeds 30% by weight, a low viscosity paste is prepared, so the aspect ratio in printing There is a problem with limit to raise

The glass frit and the additive in the composition of the second embodiment may use the same contents and ingredients as those used in the above-described first embodiment.

Therefore, the glass frit may use at least one selected from the group consisting of Bi ₂ O ₃ , Si-B-Pb, Si-Bi-Zn and Si-Pb-Al-Zn. In addition, the additive may use one or more selected from the group consisting of sintering aids, dispersants, antifoaming agents, thickeners, thixotropic agents and stabilizers.

The content of the glass frit is preferably used in 1 to 10% by weight based on the total composition. The amount of the additive is preferably used in 0.01 to 5% by weight based on the total composition.

The method of manufacturing the conductive paste composition may be prepared using a mixer used for preparing the paste. In addition, the glass frit is added to the vehicle consisting of a hydrophilic binder and a hydrophilic solvent and mixed firstly, the hydrophobic conductive metal and the additive may be added and mixed secondly, and then, may be manufactured through a grinding process using a grinding device. . The grinding device may be a grinding device well known in the art such as bead mill, three-roll mill and the like.

Meanwhile, according to the third embodiment of the present invention, there is provided a solar cell including an electrode formed using the conductive paste composition of any one of the compositions of the first and second embodiments described above.

It is preferable to use the electrically conductive paste composition of this invention for manufacture of the front electrode of a solar cell. In addition, in the present invention, the use of the conductive paste composition having a specific combination enables the desired line width after screen printing, thereby increasing the aspect ratio and improving the electrical characteristics. Accordingly, the present invention can provide an overall effect of excellent efficiency of the solar cell, in particular can provide a solar cell including a front electrode having an aspect ratio of 20 to 35% and a series resistance (Rs) of 3 or less.

At this time, the manufacturing method of the electrode of the solar cell can be manufactured by a method well known in the art, except for using the above-mentioned conductive paste composition. Therefore, a detailed description of the manufacturing method of the electrode of the solar cell will be omitted.

In the present invention, screen printing is performed by using a paste made of a hydrophilic conductive metal and a hydrophobic vehicle or a combination of a hydrophobic conductive metal and a hydrophilic vehicle, thereby improving the linewidth spreading to achieve a desired linewidth and achieving a high aspect ratio by implementing a fine linewidth. It is possible to improve the efficiency of the solar cell.

1 to 4 is an electron micrograph showing a cross section of the electrode according to Examples 1 to 4.
Fig. 5 is an electron micrograph showing the cross section and aspect ratio of an electrode formed using the conductive paste composition of Example 5 of the present invention.
Figure 6 shows a 3D photograph of the electrode according to Example 5.
7 and 8 are electron micrographs showing the cross section of the electrode according to Comparative Examples 1 and 2.

Hereinafter, the present invention will be described with reference to the following examples and comparative examples. However, these examples are for illustrating the present invention, but the present invention is not limited thereto.

< Example  1 to 4 and Comparative Example  1 to 2>

The conductive pastes of Examples and Comparative Examples were prepared using the compositions shown in Table 1 below. The content of each used component is shown in Table 1 (unit: wt%).

Specifically, a paste containing 1 to 3 μm of hydrophilic spherical silver particles, a hydrophobic vehicle (a hydrophobic binder and a hydrophobic solvent dissolved therein), a Bi ₂ O ₃ based glass frit, and an additive in the form of a sintering aid (ZnO ₂ ) is prepared. It was.

In addition, a paste was prepared containing 1.5-2.5 μm hydrophobic spherical silver particles, a hydrophilic vehicle (hydrophilic binder and a hydrophilic solvent in which it was dissolved), a Bi ₂ O ₃ based glass frit, and an additive in the form of a sintering aid (ZnO ₂ ). .

At this time, the spherical silver particles having hydrophobicity were those coated with a fat-based surface treatment agent (oleic acid) in a thickness of 1-2 nm. In addition, the hydrophilic vehicle was prepared by mixing hydroxypropyl cellulose and ethylene glycol, and the hydrophobic vehicle was prepared by mixing ethyl cellulose and butyl carbitol.

Paste manufacturing method is to add the glass frit to the hydrophilic vehicle or hydrophobic vehicle, and then mix them firstly by using PLM (Planetary Mixer), and then add the hydrophilic or hydrophobic silver particles and additives, and then proceed to PLM mixing secondly, this paste Was kneaded using a 3-roll mill to prepare a paste for a solar cell electrode.

< Example  5>

The same procedure as in Example 1 was carried out except that a hydrophilic surfactant was used as the hydrophilic conductive metal. That is, in order to surface-treat the hydrophilic conductive metal, 1 to 3 µm of hydrophilic spherical silver particles were surface treated with Tween 20, and then used for preparing the conductive paste composition.

Specifically, in preparing the hydrophilic surface-treated silver particles, the silver precursor (silver powder) is dissolved in an aqueous solution in which the surfactant (Tween 20) is dispersed, and the surface of the silver particles is coated on the surface of the silver particles at about 40 ° C. or less. Surface treatment proceeded. The silver particles thus synthesized are finally washed (water, alcohol) and dried (about 40 ° C.).

Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 silver
particle Hydrophilic 85 83 85 85 decimal 85 83 85 Hydrophilic vehicle A 0.65 0.85 0.65 B 5.85 7.65 5.85 Hydrophobic vehicle C 0.65 0.85 0.65 0.65 D 5.85 7.65 5.85 5.85 Bi ₂ O ₃ series
Glass frit 8 8 8 8 8 8 8 additive 0.5 0.5 0.5 0.5 0.5 0.5 0.5 A: hydroxypropyl cellulose
B: ethylene glycol
C: ethyl cellulose
D: Butyl Carbitol

< Experimental Example >

1. Solar Cell Manufacturing

The solar cell was manufactured using the electrically conductive paste of an Example and a comparative example. As a silicon substrate for printing electrodes, a polycrystalline substrate having a sheet resistance of 60 to 65 μs / □ was used, and a back Ag electrode was printed on a Si substrate. Next, the back Al electrode was dried after screen printing to overlap with a part of the dried back Ag electrode. Each paste drying temperature proceeded at 170 ° C.

Then, the conductive paste of the present invention was printed on the entire surface of the silicon substrate through screen printing and then dried. In this case, the mask for printing used a total thickness of 67 μm of 290 mesh, and the front electrode was formed by using a finger line having a width of 80 μm and a bus bar pattern having a width of 2 mm. . Next, drying was performed at 170 ° C., followed by sintering, to prepare a solar cell and to evaluate physical properties.

2. Evaluation of Solar Cell Efficiency

Evaluation of the electrical characteristics (I-V curve) of the obtained solar cell substrate was performed using a solar simulator. Also, the aspect ratio was evaluated by analyzing the printed line width and height of the electrode cross-section evaluated above. If the aspect ratio is excellent, the series resistance (Rs) of the electrode is lowered, and the effect of the solar cell is improved. The evaluation results are shown in Table 2.

In addition, cross-sectional photographs of the electrodes according to Examples 1 to 4 are shown in FIGS. 1 to 4, respectively.

Sectional photographs (including aspect ratios) and 3D photographs of electrodes formed using the conductive paste composition according to Example 5 are shown in FIGS. 5 and 6, respectively.

In addition, cross-sectional photographs of the electrodes according to Comparative Examples 1 and 2 are shown in FIGS. 7 and 8.

Example
One Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Rs (mΩ) 2.03 2.30 2.15 2.45 1.90 3.20 3.12 Isc (A) 8.36 8.31 8.35 8.28 8.38 8.15 8.18 F.F (%) 76.64 76.52 76.60 76.47 76.68 76.12 76.25 Eff (%) 16.69 16.63 16.67 16.62 16.73 16.18 16.25 Aspect ratio (%) 36.9 35.4 36.0 33.7 40.6 16.5 18.5

In Table 2 and the results of FIGS. 1-6, Examples 1-5 of the present invention include a combination of a hydrophilic metal, a hydrophobic binder, and a hydrophobic solvent, or a composition including a combination of a hydrophobic metal, a hydrophilic binder, and a hydrophilic solvent. Since it is used, it can be seen that the aspect ratio of the prepared electrode is superior to Comparative Example 1-2. Therefore, the present invention has improved the efficiency of the solar cell by lowering the Rs of the electrode. In addition, in Example 5, the surface of the hydrophilic conductive metal was used after the surface active treatment, and compared to Example 1-2, the aspect ratio after printing was further improved and Rs was very low to improve battery efficiency.

On the other hand, when the electrode is prepared using the conductive paste compositions of Comparative Examples 1 and 2 from Table 2 and the results of FIGS. 7-8, the paste may not include the same hydrophilic or hydrophobic material, and thus the printability cannot be improved. The low aspect ratio and the high series resistance make the battery less efficient. In addition, Comparative Example 1-2 uses a metal and a binder having the same characteristics, it is difficult to control the TI value and the light receiving area is reduced due to the spread of the line width, resulting in a decrease in solar cell efficiency.

Claims (15)

(a) hydrophilic conductive metals, hydrophobic vehicles, glass frits and additives, or
(b) hydrophobic conductive metals, hydrophilic vehicles, glass frits, and additives
Including;
The hydrophobic vehicle comprises a hydrophobic binder and a hydrophobic solvent,
The hydrophilic vehicle includes a hydrophilic binder and a hydrophilic solvent,
Conductive paste composition.
The method of claim 1, wherein the hydrophilic conductive metal comprises at least one member selected from the group consisting of Ag, copper, nickel, Au, and silver coated metals having an average particle diameter of 0.1 to 5 µm, which are not coated or subjected to hydrophilic surfactant treatment. Electroconductive paste composition.
The method of claim 2, wherein the hydrophilic surfactant treatment is polysorbitol, sorbitan fatty acid esters, polyglycerin (glycerol) fatty acid esters and oxyethylene (oxyethylene) A conductive paste composition that proceeds using any one or more selected from the group consisting of
The method of claim 1, wherein the hydrophobic binder is composed of acrylic resin, epoxy resin, polyester resin, polyurethane resin, amino resin, phenol resin, vinyl resin, ethyl cellulose, polymethacrylate, monobutyl ether and polyvinyl resin. 1 or more types of conductive paste composition selected from the group.
The method according to claim 1, wherein the hydrophobic solvent is selected from the group consisting of terpineol, butyl carbitol, butyl carbitol acetate, texanol, butyl cerusolve acetate, butyl celusolve, diethylene glycol ethyl ether, and hexylene glycol. A conductive paste composition which is a species or more.
The conductive material of claim 1, wherein the hydrophobic conductive metal comprises at least one metal powder selected from the group consisting of Ag, copper, nickel, Au, and silver coated metals having an average particle diameter of 0.1 to 5 μm coated with a fatty acid. Paste composition.
The conductive paste composition of claim 6, wherein the fatty acid is at least one selected from the group consisting of oleic acid, stearic acid, palmitic acid and acetic acid.
The method of claim 1, wherein the hydrophilic binder is polyethylene glycol, polyvinyl alcohol, polyvinylacetate, polyacrylamide, polyacrylic acid, polymethacrylic acid, polyethylene oxide, methyl lactate, ethyl lactate, propyl lactate, aqueous poly Conductive paste composition of at least one selected from the group consisting of urethane, hydroxyethyl cellulose, hydroxypropyl cellulose, ethyl hydroxyethyl cellulose, methyl cellulose and hydroxyalkyl methyl cellulose.
The conductive paste composition of claim 1, wherein the hydrophilic solvent is at least one selected from the group consisting of butoxyethanol, isopropyl alcohol, ethylene glycol, acetone, methanol, and ethyl acetate.
The conductive paste composition of claim 1, wherein the glass frit is at least one selected from the group consisting of Bi ₂ O ₃ , Si-B-Pb, Si-Bi-Zn, and Si-Pb-Al-Zn.
The conductive paste composition of claim 1, wherein the additive is at least one selected from the group consisting of a sintering aid, a dispersant, an antifoaming agent, a thickener, a thixotropic agent, and a stabilizer.
The method of claim 1,
40 to 90 wt% of a hydrophilic conductive metal,
1 to 20% by weight of hydrophobic binder,
1-30% by weight of hydrophobic solvent,
1 to 10 weight percent of glass frit, and
0.01 to 5 wt% additive
Conductive paste composition comprising a.
The method of claim 1,
40 to 90 weight percent of a hydrophobic conductive metal,
1 to 20% by weight hydrophilic binder,
1 to 30% by weight hydrophilic solvent,
1 to 10 weight percent of glass frit, and
0.01 to 5 wt% additive
Conductive paste composition comprising a.
A solar cell comprising an electrode formed using the conductive paste composition of claim 1.
The solar cell of claim 14, comprising a front electrode having an aspect ratio of 20 to 35% and a series resistance (Rs) of 3 or less.

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